1. Field of the Invention
The present invention relates to liquid-ejection testing methods, liquid-ejection testing devices, and computer-readable media.
2. Description of the Related Art
Inkjet printers are known as printing apparatuses for carrying out printing by ejecting ink onto various media such as paper, cloth, and film. Inkjet printers perform color printing by ejecting ink of various colors such as cyan (C), magenta (M), yellow (Y), and black (K) to form dots on the medium. Ink is ejected using nozzles.
However, in these inkjet printers, clogging can occur in the nozzles due to adherence of the ink for example, and the ink may not be ejected properly. When ink cannot be ejected properly from the nozzles, dots cannot be formed appropriately on the medium, and this results in the trouble that an image will not be printed clearly.
Thus, various methods for testing whether or not ink is properly ejected have been conventionally proposed. As one method, a testing method for optically detecting ink ejected from the nozzles has been proposed (see JP-A-2000-233520). In this testing method, a photodiode detects whether or not a beam emitted from an LED is blocked by ink ejected from a nozzle, so that whether or not ink is ejected from the nozzle is checked.
However, this testing method has the problems as follows. It is very difficult to positionally align a beam emitted from an LED and ink ejected from a nozzle. When ink is ejected from the nozzle in a curve, it is impossible to detect ink ejection, and thus it may be impossible to accurately detect whether ink is being ejected or not.